docs: def get_total_ram():
      """The total amount of system RAM in bytes.
  
      This is what is reported by the OS, and may be overcommitted when
      there are multiple containers hosted on the same machine.
      """
      with open('/proc/meminfo', 'r') as f:
          for line in f.readlines():
              if line:
                  key, value, unit = line.split()
                  if key == 'MemTotal:':
                      assert unit == 'kB', 'Unknown unit'
                      return int(value) * 1024  # Classic, not KiB.
          raise NotImplementedError()